Grain bins typically have cylindrical steel walls and conical steel roofs and are assembled on-site. The cylindrical steel wall is fashioned from curved steel panels having horizontal corrugations. Bolt holes are located about the edges of the curved steel panels so that panels can be fastened to the lower edge of an assembled roof and to each other in successive rings to complete a bin. To build a bin a circular roof is placed on the ground where the bin is to be located. The roof is lifted it off the ground with the use of jacks spaced around the circumference of the roof, and a first ring of wall panels is attached to the lower edge of the roof. To avoid over-stressing the wall panels, all the jacks must be operated in small increments or preferably simultaneously. Once connected, the roof and first ring are lifted again with the jacks and a second ring is attached to the lower edge of the first ring. The structure continues to be lifted and successive rings of panels added until the bin reaches the desired height.
This current method is difficult and labor intensive. One of the most difficult parts of bin construction is raising the successive circular rings of panels so that all parts of the structure stay level and lift at the same rate. If this is not done properly, parts of the structure will be overloaded and the structure will collapse.
Another method for building a grain bin includes the use of an overhead crane. This method is difficult because a single point suspension of a large grain bin, at the point of the conical roof, is unstable. A multi-point suspension of a large grain bin is subject to the same difficulties as a multi-point jacking operation: it's difficult to keep all parts of the structure level and to lift them at the same rate.
A related construction problem arises when building hoppers. Hoppers are grain bins with v-shaped conical bottoms for dispensing the grain into other containers using gravity. It would be desirable to build the conical bottom in place and then place add the circular steel rings and conical roof on top of it.
There is a need to provide a stable method of constructing a grain bin that is easier and less labor intensive than current methods.